Tibial tubercle osteotomy for total knee arthroplasty and instruments and implants therefor

Abstract

A method of performing a tibial tubercle osteotomy includes cutting a bone portion of a tibial tubercle from a remaining portion of the tibial tubercle, at least a portion of a patella ligament being attached to the bone portion. The bone portion of the tibial tubercle is separated from the remaining portion of the tibial tubercle such that the patella ligament remains attached to the bone portion. After completing a surgical procedure, the separated bone portion of the tibial tubercle is reattached to the remaining portion of the tibial tubercle.

1. A bone die cutter comprising:
 a housing having an interior surface bounding a chamber, the housing having an opening in communication with the chamber; 
 a first translating arm having a proximal end and an opposing distal end, the first translating arm passing through the opening of the housing such that the proximal end is disposed within the chamber of the housing and the distal end freely extends beyond the housing; 
 a second translating arm having a proximal end and an opposing distal end, the second translating arm passing through the opening of the housing such that the proximal end is disposed within the chamber of the housing and the distal end freely extends beyond the housing; 
 a cutting die disposed on the distal end of each translating arm, the cutting dies having complementary configurations and being opposing facing; and 
 means for selectively advancing at least one of the first and second translating arms toward the other so as to draw the cutting dies together without pivoting the first or second translating arms relative to each other. 
 
   
   
     2. A bone die cutter as recited in  claim 1 , wherein each die comprises a blade that terminates at a sharpened edge, the sharpened edge having a contour that corresponds substantially to the contour of the exterior surface of a vertically bisected heart design. 
   
   
     3. A bone die cutter as recited in  claim 2 , wherein the dies are positioned so that when the blades are brought together, the sharpened edges of the dies come into contact with each other substantially simultaneously along substantially the entire length of the sharpened edges. 
   
   
     4. A bone die cutter as recited in  claim 1 , wherein each die comprises an outwardly projecting blade, the dies being positioned so that the blades intersect at an angle when the blades are brought together. 
   
   
     5. A bone die cutter as recited in  claim 1 , further comprising a spacer adjustably mounted to the housing and projecting between the first and second translating arms. 
   
   
     6. A bone die cutter as recited in  claim 5 , wherein the spacer comprises a bolt in threaded engagement wit the housing. 
   
   
     7. A bone die cutter as recited in  claim 1 , wherein each translating arm has a distal end face, each cutting die being removably mounted to the distal end face of a corresponding translating arm. 
   
   
     8. A bone die cutter as recited in  claim 7 , wherein the distal end face of each translating arm is disposed in a discrete corresponding plane, the planes intersecting so as to form an inside angle in a range between about 60° to about 120°. 
   
   
     9. A bone die cutter as recited in  claim 1 , wherein the means for selectively advancing comprises a threaded shaft, the proximal end of the first and second translating arms being mounted on the shaft, selective rotation of the shaft causing at least one of the first and second translating arms to advance toward the other. 
   
   
     10. A bone die cutter as recited in  claim 1 , wherein each die comprises an outwardly projecting blade that terminates at a sharpened edge, each sharpened edge having a curved contour, and wherein the dies are positioned so that when the blades are brought together, the sharpened edges of the dies come into contact with each other substantially simultaneously along substantially the entire length of the sharpened edges. 
   
   
     11. A bone die cutter comprising:
 a housing comprising a first rail and a second rail; 
 a first translating arm having a proximal end and an opposing distal end, the first translating arm being mounted on the housing in engagement with the first rail so that the first translating arm can selectively slide in a substantially liner path along the first rail, the distal end of the first translating arm projecting away from the housing; 
 a second translating arm having a proximal end and an opposing distal end, the second translating arm being mounted on the housing in engagement with the second rail so that the second translating arm can selectively slide in a substantially linear path along the second rail, the distal end of the second translating arm projecting away from the housing; 
 a first die being mounted on the distal end of the first translating arm, the first die comprising a first outwardly projecting blade; 
 a second die being mounted on the distal end of the second translating arm, the second die comprising a second outwardly projecting blade, the first and second rails being configured to guide the first and second translating arms toward each other so that the first and second blades draw together without pivoting the first or second translating arms relative to each other. 
 
   
   
     12. A bone die cutter as recited in  claim 11 , wherein the housing comprises an interior surface bounding a chamber, the housing having an opening in communication with the chamber, the proximal end of the first and second translating arms being disposed within the chamber of the housing. 
   
   
     13. A bone die cutter as recited in  claim 11 , wherein each blade terminates at a sharpened edge, the sharpened edge having a contour that corresponds substantially to the contour of the exterior surface of a vertically bisected heart design. 
   
   
     14. A bone die cuter as recited in  claim 13 , wherein the dies are positioned so that when the blades are brought together, the sharpened edges of the dies come into contact with each other substantially simultaneously along substantially the entire length of the sharpened edges. 
   
   
     15. A bone die cutter as recited in  claim 11 , wherein each die comprises an outwardly projecting blade, the dies being positioned so that the blades intersect at an angle when the blades are brought together. 
   
   
     16. A bone die cutter as recited in  claim 11 , further comprising a spacer adjustably mounted to the housing and projecting between the first and second translating arms. 
   
   
     17. A bone die cutter as recited in  claim 11 , further comprising means for selectively advancing at least one of the first and second translating arms toward the other without pivoting the first or second translating arms relative to each other. 
   
   
     18. A bone die cutter as recited in  claim 17 , wherein the means for selectively advancing comprises a threaded shaft, the proximal end of the first and second translating arms being mounted on the threaded shaft such that selective rotation of the shaft causes at least one of the first and second translating arms to advance toward the other. 
   
   
     19. A bone die cutter as recited in  claim 11 , wherein the first and second outwardly projecting blades each terminate at a sharpened edge, each sharpened edge having a curved contour, and wherein the dies are positioned so that when the blades are brought together, the sharpened edges of the dies come into contact with each other substantially simultaneously along substantially the entire length of the sharpened edges.